Preheat oven to 375 degrees. Lightly grease a 12-cup muffin tine and line bottom and sides of cups with puff pastry. In a saucepan, combine milk, cornstarch sugar and vanilla. Cook. stirring constantly until mixture thickens. Place egg yolks in a medium bowl. Slowly whisk half of the hot milk mixture into egg yolks. Gradually add egg yolk mixture back into the remaining milk mixture, whisky constantly. Cook, stirring constantly, for five minutes or until thickened. Remove vanilla bean. Fill pastry line muffin tin with mixture and bake din preheated oven 20 minutes or until pastry is golden brown and filling is lightly browned on top.Editor's note: This story was edited at 1:52 p.m. Jan. 12 to correct the baking temperature.